Monitoring of Surface Water Quality in King Talal Dam Using GIS: A Case Study

Abstract

King Talal Dam is the largest surface water reservoir in Jordan. Zarqa River and some springs are the major flow contributors to this dam. The other inflow comes in the form of effluents from Al-Samra, Baqa'a, and Jerash wastewater treatment plants, and industries located in Amman and Zarqa. These effluents dramatically deteriorate the water quality of the dam. This study applied Geographical Information System to monitor the temporal and spatial changes in the water quality of King Talal Dam. The parameters included toxicity and infiltration risks, clogging in irrigation systems (drip), soil degradation through soluble salt accumulation, and excessive nitrogen-associated issues. The study expanded from winter 2014 to summer 2016. The final integrated maps revealed two suitable and unsuitable classes for irrigation purposes. The study also provided essential information about the main water quality parameters and pollution sources such as EC, and E. coli. They were recorded throughout the study period in unsuitable zones whereas TSS and bicarbonate (HCO3-) were found in the spring of 2015 and spring of 2016, respectively. Autumn 2014 was found to be the worst season among all the study years. During that season, the unsuitable area expanded up to 93% of the total reservoir area. Then, the unsuitable zone reached up to 68.4% of the total area during the winter of 2016. The mapping results indicated that site 100 remained polluted during all the study seasons. This was expected as site 100 is in Zarqa River where Al-Samra and Jerash wastewater treatment plants are discharged.